William Saletan writes a guide on How to Manipulate Donald Trump. Basically, Saletan says, you pat him on the head, tickle him under the chin and tell him he's great. Then he'll do anything you want.
Which would be nice if it were true. The trouble with that is there are other people with opposite goals patting him on the head, tickling him under the chin and telling him he's great. Also, I suspect you could kiss that man's ass for a month and he still wouldn't do anything that would prevent a guy like him from making as much money as possible.